This invention relates to a pipe joint for joining the ends of two pipes for hydraulic or electrical signal or energy transfer. The pipes have one or more longitudinal bores and/or lines or conduits in their walls. The joint comprises a pipe union having internal threads with one section threaded to the left and another section threaded to the right, corresponding respectively to external threads on the pipe end sections.
In production of oil and/or gas from a reservoir in a geological formation it is desirable to transfer signals concerning production and equipment parameters, or it may be desirable to transmit electrical or hydraulic energy to equipment being used in the reservoir, e.g. for controlling or operation of valves or the like. Often it may be desirable to supply a fluid to the reservoir, e.g. a tracer, a packing fluid or a solution/cleaning agent.
Previously it has been attempted to arrange lines in the walls of a production pipe in an oil/gas well, to transfer signals, energy or a liquid as mentioned above. A production pipe of this type consists of several pipe sections interconnected by pipe joints. However, these state of the art joints do not satisfy the demand of fluid tightness and do not have the necessary performance characteristics. One example of a known pipe joint is disclosed in EP 0 489 137 B1.